Process for the synthesis of hydroxyl-end group functionalized polybutadienes

Abstract

This invention relates to a process for the synthesis and purification of hydroxyl-end group functionalized, linear, non-crosslinked polyolefins without pendant chain branched groups, and specifically to hydroxyl-end group functionalized polybutadienes. The process comprises polymerizing a cyclic olefin monomer with a chain transfer agent in the presence of a suitable catalyst, thereby forming a protected end-group functionalized polyolefin, followed by adding a mixture comprising water and caustic to the protected end-group functionalized polyolefin to remove the protecting groups, thus forming a hydroxyl end-group functionalized, linear, non-crosslinked polyolefin without pendant chain branched groups.

What is claimed is:  
     
       1. A process for the preparation of an hydroxyl end-group functionalized, linear, non-crosslinked polyolefin without pendant chain branched groups comprising: 
       (I) polymerizing  
       (A) a cyclic olefin monomer with  
       (B) a chain transfer agent in the presence of  
       (C) a metathesis polymerization catalyst;  
       thereby forming a protected end-group functionalized polyolefin;  
       (II) saponifying said protected end-group functionalized polyolefin by adding  
       (D) a mixture comprising water and caustic, to the protected end-group functionalized polyolefin to remove the protecting end-groups;  
       thereby forming a hydroxyl end-group functionalized, linear, non-crosslinked polyolefin without pendant chain branched groups.  
     
     
       2. A process for the preparation of an hydroxyl end-group functionalized, linear, non-crosslinked polyolefin of  claim 1 , wherein said cyclic olefin monomer (A) comprises 1,5-cyclooctadiene. 
     
     
       3. A process for the preparation of an hydroxyl end-group functionalized, linear, non-crosslinked polyolefin of  claim 1 , wherein said chain transfer agent (B) comprises 1,4-diacetoxy-2-butene. 
     
     
       4. A process for the preparation of an hydroxyl end-group functionalized, linear, non-crosslinked polyolefin of  claim 1 , wherein said catalyst (C) comprises a ruthenium carbene catalyst. 
     
     
       5. A process for the preparation of an hydroxyl end-group functionalized, linear, non-crosslinked polyolefin of  claim 1 , wherein said mixture comprising water and caustic comprises an aqueous potassium hydroxide solution or an aqueous sodium hydroxide solution. 
     
     
       6. A process for the preparation of an hydroxyl end-group functionalized, linear, non-crosslinked polyolefin of  claim 1 , additionally comprising the steps of: 
       (III) neutralizing the resulting polymer product of said step (II) with acid; and  
       (IV) further purifying the resulting polymer product of step (III) by filtration; to obtain the hydroxyl end-group functionalized, linear, non-crosslinked polyolefin without pendant chain branched groups.  
     
     
       7. A process for the preparation of an hydroxyl end-group functionalized, linear, non-crosslinked polyolefin of  claim 1 , wherein said mixture of step (II) additionally comprises a phase transfer agent. 
     
     
       8. A process for the preparation of an hydroxyl end-group functionalized, linear, non-crosslinked polyolefin of  claim 7 , wherein said phase transfer agent is selected from the group consisting of tri-n-octylmethylammonium chloride, sodium stearate and 1,4,7,10,13,16-hexaoxacyclooctadecane.